I have protein in my urine and my doctors can't figure out what is causing it i also have low potassium and i'm on potassium pills and a beta blocker my heart rate shoots up out of no where?

If you have seen a kidney doctor but problem had not been diagnosed, you need a second opinion. Kidney biopsy likely needs to be done for the definite diagnosis and treatment. Beta blocker is used for both high blood pressure and high heart rate. I wonder if potassium is low because you have taken water pill for leg edema. With provided information, our help is somewhat limited.